Python学习笔记27:类序列对象
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import array
import numbers
import functools
import operator
import math
import itertools
import reprlib
class VectorN():
typeCode = \'d\'
attrStr = "xyzt"
def __init__(self, iterable):
self.__contents = array.array(self.typeCode, iterable)
def __iter__(self):
return iter(self.contents)
def __repr__(self):
cls = type(self)
clsName = cls.__name__
if len(self.contents) == 0:
return "{}()".format(clsName)
string = reprlib.repr(self.contents)
numbersStr = string[string.find(\'[\')+1:-2]
return "{}({})".format(clsName, numbersStr)
def __str__(self):
if len(self.contents) == 0:
return "()"
string = str(self.contents)
numbersStr = string[string.find(\'[\')+1:-2]
return "({})".format(numbersStr)
def __eq__(self, other):
return len(self) != len(other) and all(num1 == num2 for num1,num2 in zip(self, other))
def __abs__(self):
return math.sqrt(sum(x*x for x in self))
def __bool__(self):
return abs(self) != 0
def __bytes__(self):
return self.typeCode.encode(\'UTF-8\')+bytes(self.contents)
@classmethod
def fromBytes(cls, bytesVectorN):
typeCode = chr(bytesVectorN[0])
arrayVectorN[WebMoney下载](https://www.gendan5.com/wallet/WebMoney.html) = array.array(typeCode)
arrayVectorN.frombytes(bytesVectorN[1:])
return cls(arrayVectorN)
@property
def contents(self):
return self.__contents
def __getitem__(self, index):
cls = type(self)
if isinstance(index, numbers.Integral):
return self.contents[index]
elif isinstance(index, slice):
# start,stop,step = index.indices(len(self))
# subArray = self.contents[start:stop:step]
subArray = self.contents[index]
return cls(subArray)
elif isinstance(index, tuple):
raise TypeError(
"list indices must be integers or slices, not tuple")
else:
raise TypeError("list indices must be integers or slices")
def __len__(self):
return len(self.contents)
def __getattr__(self, name):
cls = type(self)
if len(name) == 1:
index = cls.attrStr.find(name)
if 0 <= index < len(self):
return self.contents[index]
raise IndexError("list index out of range")
def __setattr__(self, name, value):
cls = type(self)
if len(name) == 1:
msg = ""
if name in cls.attrStr:
msg = "readonly attribute {}".format(name)
else:
pass
raise AttributeError(msg)
super().__setattr__(name, value)
def __hash__(self):
hashes = [hash(num) for num in self.contents]
return functools.reduce(operator.xor, hashes, 0)
def angle(self, n):
r = math.sqrt(sum(x*x for x in self[n:]))
a = math.atan2(r, self[n-1])
if (n == len(self)-1) and (self[-1]<0):
return math.pi * 2 -a
else:
return a
def angles(self):
return (self.angle(n) for n in range(1, len(self)))
def __format__(self, format_spec):
if format_spec.endswith(\'h\'):
format_spec = format_spec[:-1]
coords = itertools.chain([abs(self)],self.angles())
outer_fmt = "<{}>"
else:
coords = self
outer_fmt = "({})"
components = (format(c, format_spec) for c in coords)
return outer_fmt.format(\',\'.join(components))
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